The water filtered into certain subjacent strata, which were particularly friable; the foot-way, which was of flag-stones, as in the ancient sewers, or of cement on concrete, as in the new galleries, having no longer an underpinning, gave way.

It has divided the poor into three distinct categories – "subjacent poor" living on 75 cents to $ one a day, "medial poor" living on 50 cents to 75 cents a day and "ultra poor" living on less than 50 cents a day.